Infrared radiation generator

ABSTRACT

A portable infrared heater comprises a burner capable of burning a plurality of fluid fuels individually or simultaneously and a combustion chamber lined with refractory material. Mean are provided to create a vortex of heated gases in a combustion chamber for even heating. A flue mounted wind cap permits variations of draft pressure from negative to positive values to cutoff. The combustion chamber may be open to the atmosphere for direct radiation or closed with a silicon carbide plate in which case secondary radiation is emitted from the outer face of such plate. The surfaces of the lining and the plate are textured to increase their area and radiation intensity. A stand permits radiation to be beamed in any desired direction.

United States Patent [72] Inventor Eric Colin-Smith 3,203,413 8/1965Hartzell et all 126/928 gznltgllllen Road, wellesley Hills, Mass.FOREIGN PATENTS 464,692 8/1928 Germany 1. 431/328 Sm- 23 1,106,3517/1955 France 431/328 [45] Patented Feb. 9, 1971 PrimaryExaminer--Charles .I. Myhre [54] INFRARED RADIATION GENERATOR [56]References Cited UNITED STATES PATENTS 3,139,879 7/1964 Bauer et a1126/92BX 3,229,680 1/1966 Hebert et a1. 126/92B 3,407,024 10/1968Hirschberg et al 431/328 Attorney-Douglas S. Johnson ABSTRACT: Aportable infrared heater comprises a burner capable of burning aplurality of fluid fuels individually or simultaneously and a combustionchamber lined with refractory material. Means are provided to create avortex of heated gases in a combustion chamber for even heating. A fluemounted wind cap permits variations of draft pressure from negative topositive values to cutoff. The combustion chamber may be open to theatmosphere for direct radiation or closed with a silicon carbide platein which case secondary radiation is emitted from the outer face of suchplate. The surfaces of the lining and the plate are textured to increasetheir area and radiation intensity. A stand permits radiation to bebeamed in any desired direction.

PATENIZTFUFE'B' 9m 3.561422 sum 2 or 2 w LO 1 LO Q '5 r\ INVENIOR. ERICCOLIN-SMITH 49 ,x

. PATENT AGENT INFRARED RADIATION GENERATOR SUMMARY OF THE INVENTIONThis invention relates to generators of radiation primarily radiation ofsuch wave lengths as to fall within the infrared portion of thespectrum. Such generators are commonly referred to as infrared heaters.

Infrared radiation possessesthe-capability of penetrating a transparentmedium such as air with little or no loss of energy and of imparting itsenergy content to more dense objects upon which it impinges. Thisproperty can be utilized to maintain humans comfortably warm even thoughsituated outdoors in a cold environment. This invention is directed to aheater primarily intended for such use. However it is also well adaptedfor cooking, and warming occupants of building or other habitations.

The invention described herein is a reliable, efficient generator ofinfrared radiation capable of operating with a variety of fluid fuelsincluding diesel oil, kerosene, No. 2 and No. 4 fuel oil, jet fuel,gasoline, natural gas, propane, butane and manufactured gas. Thisversatility in addition to its ability to serve as a radiant heatereitheroutdoors or indoors or as a food cooker makes it ideally suitedfor use in remote, frigid areas where the ability to utilize almost anytype of fluid fuel is a pronounced asset.

The heater comprises a burner capable of utilizing a variety of fuels.Burning gases issue from the burnerand traverse a tuyer from which theyare directed tangentially into a combustion chamber comprising abowl-shaped casing lined with a high temperature refractory material.Means are provided to ensure virtually complete combustion of fuel inthe burner and in the combustion chamber. The hotgases revolvecyclonefashion within the combustion chamber and provide substantiallyuniform heating of the lining thereof. The surface of the lining ispreferably textured by applying a corrugated or waffled design or byroughening to increase the surface area and thereby the intensity ofradiation which may emanate therefrom. I

The mouth of the combustion chamber may be left open in which caseinfrared radiation originating on the surface of the chamber lining isbeamed directly into the atmosphere.

Alternatively the mouth of the chamber may be closed by a disc ofsilicon carbide sandwiched between supporting sheets of metallic mesh.In this case infrared radiation emanates from the outer face of the discwhich may likewise be textured or roughened to increase its surface areain the same manner as the combustion chamber lining.

A flared, polished horn is mounted in spaced relation to the mouth ofthe combustion chamber and serves to concentrate and direct the beam ofinfrared rays in thedesired direction and, if used outdoors, to shieldthe radiation emitting surfaces from the cooling effects of wind.

An exhaust flue is provided through which burned gases are expelled tothe atmosphere. An adjustable cap is mounted upon the outer end of theflue. Three variations of this cap are depicted. All possess means foraltering the back pressure upon the escaping gases and for reducing thedetrimental effects of wind upon such back pressure. One variationutilizes the Venturi principle to achieve a hyperdraft within said flue.

The burner, combustion chamber and associated elements are mounted upona highly versatile stand. This stand is capable of being secured to theground by means of pegs anchored thereto by light chains. It permitsinfrared radiation emanating from the unit to be beamed in any desireddirection. Means are provided to lock the combustion chamber casing inthe desired attitude. When using the heater for cooking purposes theupwardly directed mouth of the chamber can be lowered to a convenientheight.

All adjustments of the stand and flue caps are designed to be easilymanaged by an operator wearing heavy mitts or gloves- -normal apparelfor outdoor workers in frigid environments.

DESCRIPTION OF DRAWINGS FIG. 1 is a pictorial view of the infraredradiation generator equipped with a flue cap as detailed in FIG. 2.

FIG. 2 is a vertical section of the-combustion chamber and flue captaken on the line 2-2 of FIG. I.

FIGS. 3 and 4 disclose alternative flue caps.

FIG. 5 is a central sectional view of the burner mechanism.

FIG. 6 is a sectional view taken on the line 6-6 of FIG. 5.

DESCRIPTION OF INVENTION The invention comprises a stand l'consisting ofa square base plate 2 to which is hinged adjacent each of the four edgesthereof an articulated foot 3 composed of inner and outer elements 3aand 3b respectively pivotally connected by a hinge 4. When aligned,elements 3a and 3b may be locked in position by a U-shaped clevis 5inserted into mating apertures 6a and 6b in such elements. The clevis isanchored to the element 311 by a light chain 7. An opening 8 bushcd witha hardened steel liner 9 is provided adjacent the outer end of each ofthe elements 3b. Pegs l0 anchored by light chains II to elements 3b maybe inserted through the liners 9 to secure the feet to the ground. Ifused indoors appropriate fastening means such as bolts or screws may besubstituted for the pegs 10.

A collar 12 cast integral with the plate 2 or welded thereto forms, inconjunction with such plate, a socket 13. A post 14 seated in suchsocket may be locked in position by a hand screw 15. The post 14 isprovided with a vertical row of openings 16 each extending diametricallytherethrough.

A sleeve 17 slidably mounted upon the upper portion of the post 14 has ahole 18 drilled diametrically therethrough which may be brought intoregister with any one of the openings 16. A pin 19 attached to thesleeve by a light chain 20 may be inserted through the hole 18.into anyone of such openings. By choosing different openings the elevation ofthe sleeve 17 upon the post 14 may be adjusted. Handles 21 attached toopposite sides of the sleeve 17 facilitate such adjustment.

A short cylindrical member 22 having an integral collar 23 is rotatablyseated within the upper end of the sleeve I7. A hand screw 24 permitssuch member to be locked in any desired position in the plane ofrotation thereof. Arms 25 project outwardly and upwardly from the member22 and carry aligned bearings 26 at the extremities thereof. Each suchbearing is equipped with a locking screw 27. The hand and locking screws15, 24 and 27 are anchored through swivels 28 and light chains 29 toadjacent members respectively.

The base plate 2, feet 3, collar 12, post 14 and sleeve I7 arepreferably composed of a lightweight material such as aluminum oraluminum alloy to render the unit more easily portable.

A generally bowl-shaped shell 30 composed of metal capable ofwithstanding high temperatures without deformation is located betweenthe bearings 26. While this configuration is to be preferred the shell30 may be otherwise shaped. For exam ple it may be cylindrical orconical or rectilinear while maintaining roughly the same mouth area tolinear depth relationship. Any such form will yield generallysatisfactory results. Trunnions 31 secured to either side of the shell30 threadably receive shafts 32 journaled within the bearings 26. Eachsuch shaft has a handle 33 affixed to the outer end thereof. It will beapparent that by loosening the screws 27 and turning handle 33 the shell30 may be rotated in a plane normal to that of the base plate 2. Withreference to FIG. 2 of the drawings it will be noted that a flange 34encircles the mouth 35 of the shell 30. At the opposite end of the shella vent 36 is provided around which is attached by welding or othersuitable means a flue 37 which serves to connect the interior of theshell 30 with the outer atmosphere. A further opening 38 of ovoid shapeis provided in the wall of the shell 30 through which heated gasesemerge tangentially into such shell in a manner to be described morefully hereinafter.

The interior of the shell 30 is heavily lined with an insulatingrefractory material 39 held in place by a multiplicity of metallie hooks40 welded to the inner wall of the shell. The refractory material 39should be castable, light in weight, mechanically strong and low in heatconductivity. Such a material is commercially marketed under thetrademark Kast-o-lite although other materials possessing the propertiesmentioned will be equally satisfactory.

The surface of the coating is preferably textured as at 41 by applying acorrugated or waffle design or by otherwise roughening to increase thearea thereof. The shell 30 contains the combustion chamber 42.

The mouth 35 of the shell may be closed by a plate composed of materialof high heat permeability preferably a silicon carbide disc 43sandwiched between sheets 44 of metallic mesh. These elements areclamped between encircling rims 45. The faces of the disc are preferablytextured in a manner similar to that of the surface of the lining 39.

A cylindrical spacing member 46 provided with slots 47 is mountedoutwardly of the silicon carbide disc 43 and is encircled by an integralwind screen 48 likewise slotted as at 49.

A plurality of sleeves 50 are equispaced around the member 46 and extendthrough and are affixed to annular flanges 51 encircling such member. Itwill be noted that the sleeves project a short distance forwardly of theoutermost flange as at 52.

A flared, internally polished horn 53 is mounted forwardly of the member46. Because of the sleeve projections 52 a gap 54 exists between theprojecting rim 55 forming part of the horn 53 and the outermost flange51.'The horn 53, spacing member 46 and rims 45 are secured to the flange34 by bolts 56 extending through the sleeves 50. Shorter bolts 57 usedin the vicinity of housing 79 fail to extend through the flange 34 butserve to secure the remaining elements. The purpose of the spacingmember 46, the horn 53 and the gap 54 therebetween will be explainedhereinafter.

As illustrated in FIGS. 1 and 2 the horn 53 is straight sided with amedium flare. This flare may be increased or decreased to disperse orconcentrate the infrared beam or the horn sides may be curved outwardlyor inwardly to achieve the same objectives.

The flue 37 is illustrated as a straight cylindrical member externallythreaded for the major portion of its length. it should be noted howeverthat the unthreaded section may be elongated and arranged in the form ofa rigid or semirigid elbow if desired for reasons to be later explained.

An adjustable cap 58 comprises a collar 59 threadably mounted upon theflue 37 and equipped with a locking screw 60 for the purpose of clampingthe collar at any desired location along the threaded portion of suchflue.

Angular brackets 61 are attached to the collar 59 to the outerextremities of which is bolted or otherwise affixed a plate 62 the innerface of which is of convex configuration. An upright post 63 having aslot 64 therein projects from the center of the outer face of suchplate. Web members 65 support the post 63 and serve to stiffen theplate.

A second convex plate 66 integral with an internally threaded collar 67and provided with stiffening gussets 68 is threadably mounted upon theouter end of the flue 37 in opposed relation to the plate 62. The collar67 is threaded onto the flue 32 until the outer surface thereof is flushwith the end of the flue. It is then locked in position by set screws69. It will be apparent that by rotating the outer plate 62 andassociated brackets 61 and collar 59 such plate can be caused to advancetoward or retract from opposing plate 66. This adjustment is facilitatedwhen cap 58 is hot by turning the post 63 with a bar or any similar toolinserted into the slot 64.

Due to the configuration of plates 62 and 66 air moving therebetweencreates a negative pressure at the mouth 70 of the flue in accordancewith the well-known Venturi principle. This pressure will vary dependingupon the velocity of the air passing between the plates and the spacingthereof. By narrowing the gap a positive pressure can be achieved at themouth 70 and by closing the gap the purpose of the flue can be defeated.This may be desirable in certain circumstances to be later described.

A first alternative flue cap of somewhat simpler construction isillustrated in FIG. 3. The collar 59a is threadably mounted upon theflue 37 in the same manner as the collar 59 and carries a similarlocking screw 60a. A plurality of parallel spaced bars 71 support a flatcircular disc 72 carrying on its outer face a slotted post 63a and webmembers 65a similar to the post 63 and web members 65 of FIG. 2. lt willbe apparent that by axially rotating the disc 72 and associated elements59a and 71 the inner face of the disc will advance toward or retractfrom the mouth of the flue. By this means back pressure upon gasesissuing from the flue can be adjusted.

A second alternative flue cap is illustrated in FIG. 4. In this instancethe internally threaded collar 59b and clamping screw 60b are identicalto the corresponding elements in FIGS. 2 and 3.

Short turned straps 73 are attached to .the outer wall of collar 59b andproject beyond the end thereof. These straps support a conical hood 74in spaced relation to the end of the collar enabling gases issuing fromthe mouth of the flue 37 to escape between the outer edge of the collar59b and the inner surface of the hood 74.

A plurality of studs 75 project radially from the outer surface of thecollar 59b and carry a circular metallic band 76. The band is so locatedthat it overlaps the edge of the hood 74. The combination operates toprevent wind from blowing into the collar and creating unwanted andspasmodic back pressure. However desirable back pressure may be achievedby rotating the cap embodiment upon the flue 37 thereby causing the hoodto advance toward or retract from the mouth of such flue.

A firebrick tuyer 77, rectangular in cross section. is snugly fittedagainst the outer surface of the shell 30. A flared throat 78 extendsaxially through the tuyer and connects at its larger end with theopening 38 in the wall of the shell 30. The tuyer is fixed in positionby a closely fitting metal housing 79 preferentially bolted to the shelland so positioned that gases flowing through it enter the shelltangentially.

A burner 80 illustrated most clearly in FIGS. 5 and 6 is bolted to thehousing 79 in axial alignment with the tuyer 77.

The burner consists of a substantially cylindrical casing 81 to which isintegrally attached an air inlet conduit 82 equipped with a flange 83. Adamper plate 84 provided with an integral upstanding lug 85 isfrictionally held against the face of the flange 83 by a single wingheaded bolt 86. The position of the damper plate upon the flange may beadjusted to variably control the volume of air entering the conduit 82.The lug 85 facilitates such adjustment by an operator wearing heavygloves or mitts. Under certain circumstances it may be desirable toforce air into the conduit 82. For this purpose a flanged air hose 87 isshown in FIGS. 1 and 2 is bolted to the flange 83 in place of the damperplate 84.

A cylindrical inner wall 88 terminating short of the open end of thecasing 81 is provided with rows of air vents 89. The free end of thewall 88 is surrounded by a removable metallic ring 90 maintained inposition by grub screws 91 This ring, the casing 81 and the wall 88bound a substantially annular chamber 92.

Due to this construction air entering the conduit 82 must necessarilypass through the vents 89 in order to reach the intenor of thecylindrical wall for combustion purposes. Ring 90 is intended for useprimarily when pressurized air is introduced through conduit 82. Withthis exception the ring may be dispensed with if desired.

A circular gas ring 93 provided with a series of jets 94 is centrallymounted within the end wall of the casing 81. Gas may be supplied to thering through conduit 95.

Alternate gas rings are shown at 93a and 93b with gas supply conduits95a and 95b respectively. in the case of the alternate gas ringsopenings (not shown) are provided in the end wall of the casing 81 toadmit the gas supply conduits 95a and 95b. Further openings (not shown)are located in the wall 88 for the passage of conduit 95a and in thering 90 (if used) to accommodate conduit 95b.

Both gas rings 93a and 93b are provided with a multiplicity of jetsaimed partially toward the axis of the casing 81 and partially towardthe open end thereof as illustrated at 96. The ring 93a is also providedwith a less number of rearwardly directed jets as shown at 97.

An oil burner nozzle 98 is concentrically mounted within the gas ring93. An oil supply line 99 and an air line 100 are connected to thenozzle in the usual manner.

igniting electrodes 101 passing through cylindrical insulators 102 aresupplied with current at high voltage through the conductors 103. Theelectrodes are gapped immediately in front of the oil burner nozzle asshown in FlGS. 5 and 6.

An annular recess 104 is formed in the outer wall of the easing adjacentthe open end thereof. A flexible band 105 provided with a series ofequispaced openings 106 is slidably mounted within such recess. Matchedopenings 107 are located in the casing. By adjusting the band theopenings may be continuously varied from fully open to fully closed.When the desired adjustment has been achieved the band may be locked inposition by tightening the winged clamping screw 108 as shown in FIG. 2.

Gas may be supplied to the burner 80 from any available supply such asgas mains or pressure bottles. Appropriate con nections are made to thegas supply conduits 95, 95a and 95b.

Oil under pressure is applied to the oil burner nozzle 98 through thesupply line 99. The oil may be contained in a tank (not shown) withpressure generated by a motor driven pump (not shown). Forced air issupplied to the hose 87 and air line 100 from blowers or air pumps(not'shown). The flow in all fluid lines is controlled by valves in theusual manner.

The electrodes 101 are excited by a source of high voltage current suchas a transformer capable of generating a voltage of sufficient magnitudeto breach the gap between such elec trodes.

The invention operates in the following manner:

When being transported the feet 3 are compactly folded against the post14 and sleeve 17. When it is desired to mount the unit in the open thefeet are unfolded as shown and spiked to the ground by pegs 10. Whenused indoors bolts or screws may be substituted for the pegs.

If the burner is to be gas operated this fuel is introduced throughconduits 95, 950 or 95b depending on whether gas rings 93, 93a or 93bare to be used. The ring 93 is preferred but either of the twoalternatives yield highly satisfactory results. The backward directedjets 97 of rings 93a facilitate ignitionby electrical means. Ring 9312lends itself to ignition by manual means such as by the insertion of alighted match or taper through one of the sets of like openings 106 and107.

With ring 90 in the position illustrated in H6. 5 combustion supportingair flowing through the conduit 82 must necessarily traverse the vents89 to reach the interior of the cylindrical wall 88 wherein combustionoccurs. During operation the temperature of the wall will be raised withconsequent preheating of air passing through the vents thereby enhancingthe efficiency of the burner. When using ring 93b little or nocombustion will occur within the confines of the cylindrical wall 88 andconsequently no marked preheating of combustion supporting air will takeplace. However use of this ring is desirable where manual ignition isnecessary.

Air may be permitted to flow into the conduit 82 under atmosphericpressure alone and the volume of such flow' may be varied by adjustingthe damper 84. Alternatively air may be directed into the conduit underpositive pressure through the hose 87.

When it is desired to burn oil this fuel is admitted under pressurethrough supply line 99 and air is likewise forced through line 100. Anatomized oil and air mixture emerges from the nozzle 98 and iselectrically ignited by a voltage discharge across electrodes 101 in theusual manner. If required, preheated air for combination with themixture is obtained in the same manner as with the use of gas and gasrings 93 and 93a.

Under certain circumstances when both gaseous and liquid fuels areavailable and when maximum infrared radiation is desired, gas may besupplied to one or more of the gas rings and oil to the nozzle 98 andboth fuels may be burned simultaneously.

Under other circumstances if a gaseous fuel and a source of pressurizedair is available the burner will perform satisfactorily with gassupplied to one of the gas rings and air introduced through the oilnozzle air line 100. In this instance it may be unnecessary to supplyair through the conduit 82 or air supplied through the nozzle may beauxiliary to that admitted by such conduit.

lmproved burner performance may be achieved by admitting additional airthrough the matched openings 106 and 107. The volume of air so admittedmay be varied by sliding the flexible band inits recess and locking itin position by the winged clamping screw 108 when the desired adjustmenthas been achieved.

By providing a variety of gas rings and multiple air admission means inaddition to a fluid fuel nozzle the burner is capable of highlysatisfactory operation with a variety of fuels ranging from gasoline,natural gas, propane, butane and manufactured gas on the one hand to No.2 and No. 4 fuel oil, diesel oil, jet fuel and kerosene on the other.Even crankcase oil from internal combustion engines will yield tolerableresults.

Following ignition flaming fuel-issues from the burner into the flaredtuyer throat 78 from which it emerges into the combustion chamberwherein the final stages of combustion occur. The variety of fuelinletand air inlet means in addition to draft regulation later describedpermits a multiplicity of variations of fuels and fuel mixtures andcombustion chamber pressures ensuring that the right combination forcomplete combustion can be achieved.

Assuming that the combustion chamber is closed by the disc 43 theflaming products issuing from the tuyer will create a vortex whirlingcyclonelike against the coating 39 while spiralling toward the flue 37through which they will discharge to the atmosphere. This results inuniform heating of the interior surfaces of the lining 39 and of thedisc 43.

The combination of radiation impinging against the inner face of thedisc and heated gases whirling thereacross quickly brings and maintainsthe disc at a temperature most favourable for producing infraredradiation from its outer face in copious quantities. This temperaturehas been determined as between l,625 F. and l,750 F. although a widetemperature variation will yield satisfactory results.

The spacing member 46 and the horn 53 perform a dual function. Theyprevent wind from cooling the face of the disc and also serve to directthe rays emanating from the disc in the desired direction. In additionthe member 46 and gap 54 reduce heating and consequent discoloration ofthe internally polished horn by conduction from the shell 30.

The heater may be used without the disc 43. The mesh 44 will thenincandesce and emit infrared radiation and in addition radiationgenerated within the combustion chamber will escape through theinterstices in the mesh. Under these circumstances the mesh serves as aneffective wind barrier.

When it is desired to use the heater for cooking the post 14 and sleeve17 may be removed and the member 22 seated within the socket l3 toreducethe height of the unit. The casing 30 will then be positioned with itsmouth directed upwardly. The disc 43, mesh 44, spacing member 46 andhorn 53 may be removed and replaced with a stout grill (not shown) tosupport cooking vessels. When so used the flue 37 may be closed in amanner to be later described.

In order to achieve optimum performance from the invention, irrespectiveof the type of fuel or fuels used, the fuel pres sure and combustionsupporting air pressure it is necessary to regulate the flue draft. Thecap 58 permits a wide variation in flue draft pressure.

The axis of the threaded portion of the flue 37 is vertically disposed.This may be achieved, after directing the casing 30 in the desireddirection. by inserting a rigid elbow or adjusting a semirigid elbow inthe unthreaded portion of the flue 37. When the opposed convex plates 62and 66 are spaced as illustrated in FIG. 2 a distinct negative pressurewill be developed at the mouth 70 of the flue by wind blowing betweensuch plates from any compass direction. Negative pressure can bedeveloped at the mouth of any conduit by the action of a stream of airblowing thereacross. In the present instance however the effect isgreatly enhanced by the employment of oppositely convex plates 62 and 66which utilize the Venturi principle to increase the air velocity acrossthe mouth 70 in relation to its normal velocity. A hyperdraft is therebyachieved. If maximum draft is required the upper plate 62 is rotatedthereby varying the spacing between the plates until the desired resultis attained. The collar 59 may be then locked in position by screw 60.

In order to reduce the draft the spacing between the plates is graduallydecreased. A point will then be reached at which a positive pressurewill be exerted against the gases issuing from the flue. This conditionmay be necessary for maximum burner efficiency with certain types offuels and certain combustion air pressures.

The gap between the plates may be further reduced until contact thereofoccurs. The plate 62 will then act as a closed valve to block the flue.This arrangement would be adopted for instance, when the heater is usedfor cooking purposes as previously described.

Back pressure and valve action can be similarly controlled by the capsillustrated in FIGS. 3 and 4. Some negative pressure will be developedat the mouth of the flue in FIG. 3 due to air moving thereacross. Thisnegative pressure will not reach the level achieved by the cap shown inFIG. 2 due to the absence of any Venturi action. However the cap of FIG.3 is simpler and more economical to construct.

The cap illustrated in FIG. 4 possesses means for adjusting the backpressure in the flue 37. This cap however, is particularly useful, dueto its sheltering elements, in preventing downdrafts within the flue ingusty environments.

The invention described herein is a portable, efficient generator ofinfrared radiation adapted to burn a variety of required, to the outeratmosphere.

lclaim:

I. An infrared radiation generator comprising a fluid fuel burner, meansfor admitting fuel into said burner, means for admitting air into saidburner, a combustion chamber provided with a radiation emitting opening,refractory material lining said chamber, said material being adaptedwhen heated to a predetermined temperature by combustion productsissuing from said burner to emit abundant radiation in the infraredportion of the spectrum; an exhaust flue connecting said combustionchamber with the outer atmosphere and high heat permeability meansclosing said radiation emitting opening and means for varying the draftpressure in said flue to create, in combination with air movingexternally of said flue. a hyper-draft therein. I

2. An infrared radiation generator as claimed in claim I in which saidhigh heat permeability means is composed of silicon carbide.

3. An infrared radiation generator comprising a fluid fuel burnercapable-of burning a plurality of fuels, means for admitting fluid fuelinto said burner, means for admitting air into said burner, a combustionchamber provided with a radiation emitting opening, means for causingcombustion products issued from said burner to form a vortex within saidchamber, refractory material lining said chamber adapted, when heated toa predetermined temperature, to emit abundant radiation in the infraredortion of the spectrum, the surface of said refractory ma enal beingtextured, an exhaust flue connecting said combustion chamber with theouter atmosphere and high heat permeability means closing said radiationemitting opening; said high heat permeability means being composed ofsilicon carbide and the outer face of said high heat permeability meansbeing textured and means for adjusting the draft pressure in said flueto create, in cooperation with air movement external to said flue, ahyper-draft in said flue.

4. An infrared radiation generator as claimed in claim 3 in which saidmeans for adjusting the draft pressure in said flue, when substantiallyvertically disposed, will respond to air movement from any compassdirection.

5. An infrared radiation generator as claimed in claim 4 provided withsupport means permitting radiation emanating from said generator to bebeamed in any desired direction and further means for locking saidgenerator in the position so chosen.

6. An infrared radiation generator as claimed in claim 4 in which saidplurality of fuels may be burned simultaneously.

1. An infrared radiation generator comprising a fluid fuel burner, meansfor admitting fuel into said burner, means for admitting air into saidburner, a combustion chamber provided with a radiation emitting opening,refractory material lining said chamber, said material being adaptedwhen heated to a predetermined temperature by combustion productsissuing from said burner to emit abundant radiation in the infraredportion of the spectrum; an exhaust flue connecting said combustionchamber with the outer atmosphere and high heat permeability meansclosing said radiation emitting opening and means for varying the draftpressure in said flue to create, in combination with air movingexternally of said flue, a hyper-draft therein.
 2. An infrared radiationgenerator as claimed in claim 1 in which said high heat permeabilitymeans is composed of silicon carbide.
 3. An infrared radiation generatorcomprising a fluid fuel burner capable of burning a plurality of fuels,means for admitting fluid fuel into said burner, means for admitting airinto said burner, a combustion chamber provided with a radiationemitting opening, means for causing combustion products issued from saidburner to form a vortex within said chamber, refractory material liningsaid chamber adapted, when heated to a predetermined temperature, toemit abundant radiation in the infrared portion of the spectrum, thesurface of said refractory material being textured, an exhaust flueconnecting said combustion chamber with the outer atmosphere and highheat permeability means closing said radiation emitting opening; saidhigh heat permeability means being composed of silicon carbide and theouter face of said high heat permeability means being textured and meansfor adjusting the draft pressure in said flue to create, in cooperationwith air movement external to said flue, a hyper-draft in said flue. 4.An infrared radiation generator as claimed in claim 3 in which saidmeans for adjusting the draft pressure in said flue, when substantiallyvertically disposed, will respond to air movement from any compassdirection.
 5. An infrared radiation generator as claimed in claim 4provided with support means permitting radiation emanating from saidgenerator to be beamed in any desired direction and further means forlocking said generator in the position so chosen.
 6. An infraredradiation generator as claimed in claim 4 in which said plurality offuels may be burned simultaneously.